This project assesses the effect of the family's mode of subjectively construing its social world on its participation in a family-oriented in-patient treatment program. Further, it studies more general relationships between the family-- considered as a unitary group--and formal organizations, as exemplified by the psychiatric hospital. Thirty-eight families of adolescents were selected for intensive, shorter-term longitudinal study. First, their typical mode of construing a social environment was assessed in a laboratory problem-solving situation. Then, the family's shared conception of the hospital--its staff, other patients and other participating families--was assessed through modified Q-sort and role repertory procedures. Its engagement in the treatment program was directly measured by observing its interaction patterns, expressed cohesiveness and sociometric position in the multiple family group conducted on the in-patient service. Finally therapeutic outcome was assessed through evaluation of discharge status of identified patient and family. Preliminary results suggest that the family--as a group--precisely regulates the interaction with and involvement in the social community of the ward by all of its members.